174.5 MHz Radio Telescope
North 53deg 22min 20.0sec West 02deg 12min
A paper roll chart
recording 1998-07-07-2200hr UT + 6 hours
The Radio Telescope homepage signifies an
equatorial period of 18 minutes, however the source Cygnus-A at 40deg N
has a longer period on the chart of about 30 minutes owing to the
convergence of the Hour Lines towards the celestial N-pole.
Link to a diagram which
shows how two separated (and coupled aerials) provide a virtual grating
on the Sky.
link to Journal "Nature" Vol.161, No.4087, pp.312-313 (28 Feb 1948)
Astronomers J.G.Bolton & G.J.Stanley